Respuesta :

the answer is D I really hope this helps
:)

[tex]\begin{cases}3x+6y=36\\3x-6y=0\end{cases}\\\\--------(-)\\\\3x-3x+6y-(-6y)=36-0\\\\6y+6y=36\\\\12y=36\quad|:12\\\\\boxed{y=3}\\\\\\3x-6y=0\\\\3x-6\cdot3=0\\\\3x-18=0\quad|+18\\\\3x-18+18=0+18\\\\3x=18\quad|:3\\\\\boxed{x=6}[/tex]

Answer A.